\Header{lset}{Simple Interfaces to modify Trellis Settings}
\alias{col.whitebg}{lset}
\keyword{dplot}{lset}
\begin{Description}\relax
A (hopefully) simpler alternative interface to
\code{trellis.par.get/set}. NOT S-compatible\end{Description}
\begin{Usage}
\begin{verbatim}
lset(theme, warn = TRUE)
col.whitebg()
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{theme}] a list decribing how to change the settings of the
current active device. Valid components are those in the list
returned by \code{trellis.par.get()}. Each component must itself be
a list, with one or more of the appropriate components (need not
have all components). Changes are made to the settings for the
currently active device only.

\item[\code{warn}] logical, whether a warning should be issued when
\code{trellis.par.get} is called when no graphics device is open 
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
\code{lset} essentially does the same thing as \code{trellis.par.set},
but is different in that it allows setting more than one parameter at
a time, and also that each component need have only the components
that need to be changed. 

This function is expected to be used mostly in conjunction with
functions that return `themes', i.e., lists which when supplied to
\code{lset} change the overall look and feel of the display.

\code{col.whitebg} is one such function, which returns a list which
when supplied to \code{lset} changes the background to transparent and
the other colors to something suitable. Contributions of more such
`themes' are welcome.\end{Details}
\begin{Author}\relax
Deepayan Sarkar \email{deepayan@stat.wisc.edu}\end{Author}
\begin{SeeAlso}\relax
\code{\Link{lattice.theme}}, \code{\Link{show.settings}},
\code{\Link{Lattice}}\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
show.settings(col.whitebg())
# The following reproduces Splus Unix black and white pch:
#lset(list(superpose.symbol=list(pch=c("o","+",">","s","w","#","{"))))
\end{ExampleCode}
\end{Examples}

